The goal of project 1 is to intensively phenotype Mexican American (MA) families which have been ascertasined via an index case with coronary artery disease (CAD) in order to investigate physiologic and genetic interrelations between insulin resistance (IR), the insulin resistance syndrome, and athersclerosis. We hypothize that there is a strong basis for IR, components of the metabolic syndrome, and CAD, and that IR and the metabolic syndrome are major contributing factors to CAD in MA.